400339 ÷ 87 
We're looking to find how many times 87 goes into 400339.

On to step 1:
If we divide 4 by 87, we get 0 and a remainder of 4.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 4 to get 4.
Include the next digit (0) from the dividend after 4, then repeat: 40 / 87

Going ahead to step 2:
If we divide 40 by 87, we get 0 and a remainder of 40.
Write down 0 as next digit of the result. 
Result so far: 0.0
The remainder is 40 after subtracting 0 from 40.
Fetch the next digit (0) from the dividend, attach it to 40 and continue: 400 / 87

Advancing to step 3:
87 can be fit into 400 4 times, resulting in a remainder of 52.
The next digit of our result is 4. 
Result so far: 4.0
If we subtract 348 from 400, we get 52.
Append the next digit (3) from the dividend to 52 and continue with: 523 / 87

Moving on to step 4:
523 divided by 87 is 6 with a remainder of 1.
Use 6 as the next digit of our solution. 
Result so far: 46.0
If we take 522 away from 523, we end up with 1.
Grab the next digit (3) from the dividend, add it to 1, then carry on: 13 / 87

Let's proceed to step 5:
When dividing 13 by 87, we get 0 with a remainder of 13.
Use 0 as the next digit of our solution. 
Result so far: 460.0
If we take 0 away from 13, we end up with 13.
Take the next digit (9) from the dividend and append it to 13, then repeat: 139 / 87

Advancing to step 6:
The number 87 fits into 139 1 times, leaving a remainder of 52.
Record the quotient 1 as the next digit in the result. 
Result so far: 4601.0
If we subtract 87 from 139, we get 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Advancing to step 7:
The number 87 fits into 520 5 times, leaving a remainder of 85.
Put 5 as the next digit of the answer. 
Result so far: 4601.5
If we take 435 away from 520, we end up with 85.
Since there are no more digits in the dividend, we add a zero to the remainder making it 850, and continue the process.

Step 8:
The number 87 fits into 850 9 times, leaving a remainder of 67.
Use 9 as the next digit of our solution. 
Result so far: 4601.59
Subtract 783 from 850 to get 67.
Since there are no more digits in the dividend, we add a zero to the remainder making it 670, and continue the process.

Going ahead to step 9:
If we divide 670 by 87, we get 7 and a remainder of 61.
Write down 7 as next digit of the result. 
Result so far: 4601.597
If we take 609 away from 670, we end up with 61.
Since there are no more digits in the dividend, we add a zero to the remainder making it 610, and continue the process.

Step 10:
The number 87 fits into 610 7 times, leaving a remainder of 1.
Put 7 as the next digit of the answer. 
Result so far: 4601.5977
If we subtract 609 from 610, we get 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

After the division, we end up with 4601.5977 and a remainder of 1e-05.